UNITED NATIONS/AMMAN: U.S. Ambassador to the United Nations Nikki Haley warned Monday that Washington “remains prepared to act if we must,” if the U.N. Security Council fails to act on Syria, as the Syrian army’s onslaught in Eastern Ghouta continued unabated.

The United States asked the Security Council to demand an immediate 30-day cease-fire in Damascus and rebel-held Eastern Ghouta, where the Syrian army’s onslaught has killed around 1,160 people since Feb. 18.

“It is not the path we prefer, but it is a path we have demonstrated we will take and we are prepared to take again,” Haley told the 15-member Security Council. “When the international community consistently fails to act, there are times when states are compelled to take their own action.”

Russia and Damascus say a cease-fire ordered by the U.N. Security Council does not protect the fighters in Eastern Ghouta, arguing that they are members of banned terrorist groups.

“There has been no cessation of hostilities,” U.N. Secretary-General Antonio Guterres said Monday.

“Violence continues in Eastern Ghouta and beyond – including in Afrin, parts of Idlib and into Damascus and its suburbs.”

“No sieges have been lifted. ... To our knowledge, not one critically sick or wounded person has yet been evacuated.”

The assault on Ghouta is one of the heaviest in the war, which enters its eighth year this week.

Thousands of families are sleeping in the open in the streets of the biggest town in the enclave, where there is no longer any room in packed cellars to shelter from government bombardment, local authorities said.

At least 70 people had been buried in a town park because airstrikes made it unsafe to reach the cemetery on the outskirts, it said.

The Britain-based Syrian Observatory for Human Rights activist group reported that hundreds of people protested in the town of Kafr Batna to demand a deal to end the onslaught, in an apparent sign of local discontent with the rebel policy of holding out.

Shots were fired at the crowd by unidentified individuals and one person was killed, the observatory said.

Jaish al-Islam, one of Eastern Ghouta’s main rebel groups, said Monday that it had reached an agreement with the government’s ally Russia to evacuate wounded people, after communicating with Moscow through the United Nations.

A U.N. humanitarian spokeswoman said the United Nations was not part of that deal and still called for the urgent evacuation of more than 1,000 sick and wounded people from Eastern Ghouta.

State-run Syrian TV broadcast footage showing a group of men, women and children it says left the town of Madyara after it was captured by Syrian troops Sunday. It showed women carrying babies and welcoming the Syrian army, and claiming the rebels were preventing civilians from leaving the enclave.

The observatory said Monday that the death toll in the civil war had passed half a million people.

It has confirmed the deaths of 511,000 people, it said, and has the names of more than 350,000 of them. About 85 percent were killed by government forces and their allies, it said.

Meanwhile, a Turkish government spokesperson said Monday that Turkey will soon clear the Syrian town of Afrin of militants and has already gained control of more than half the area. The observatory reported hundreds of civilians fleeing the Turkish-led offensive to the government-held area of Nubul.

In other developments, Syrian jets also struck rebel-held towns in the country’s south, the first aerial attacks on the area since the United States and Russia brokered a deal making it a “de-escalation zone” last year, rebels and residents said.

The U.S. State Department said late Monday that Washington was “very concerned” by the reports of the strikes and called an urgent meeting in Jordan to assess the situation in southeast Syria.

One rebel commander said the strikes in the south appeared to be a warning to rebels under the Free Syrian Army umbrella who were planning to wage an offensive in the coming days to relieve pressure on their comrades in Eastern Ghouta.